Devices that protect and conceal a crown when it is not being used, which means most of the time that a wristwatch is used, are already known. These devices are provided for essentially technical reasons, for example to prevent the crown catching and inadvertently switching on a function, or, even worse, damaging the winding stem.
The best known method consists of providing lugs on the middle part, on either side of the crown, said lugs extending as far as the head of the crown and only leaving one portion of the notched crown visible. A device of this type is clearly shown in the Figures of CH Patent No. 515 541, even though protection of the crown is not the feature of the invention concerned.
In addition to appearing unattractive, this solution has the drawback of making it awkward to manipulate the crown, particularly pulling it.
CH Patent No. 567 300 discloses a device for locking the push buttons and crown of a chronograph wristwatch by means of a cover secured to a rotating bezel including an extension extending beyond the middle part and including a vertical cylindrical wall substantially matching the height of the middle part. This solution is satisfactory for the desired object, but has the drawback of making the rotating bezel totally unusable for the usual functions of a rotating bezel.